One sided thin film capacitive touch sensors

ABSTRACT

Thin film capacitive touch sensors and applications thereof are described herein. Embodiments include construction of one-sided and two-sided thin film capacitive touch sensors with partial fill patterns, one-sided thin film capacitive touch sensors including conductive ground plane layers, one-sided thin film capacitive touch sensors including air gap layers, one-sided thin film capacitive touch sensors including a combination of both separation layers to create air gap layers and conductive ground plane layers.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of and claims priority to co-pendingNonprovisional application Ser. No. 13/104,878, filed 10 May 2011, whichin turn claims priority to U.S. Provisional Application No. 61/333,195filed on May 10, 2010, all of which are incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to capacitive touch sensors. Moreparticularly, the present invention relates to one-sided thin filmcapacitive touch sensors.

BACKGROUND

Capacitive touch sensors are known and ubiquitous. Their basic operationis relatively simple. A capacitive touch sensor typically is a smallcapacitor enclosed in an electrical insulator. The capacitor is a devicethat has an ability to store an electrical charge, referred to ascapacitance. When a power source applies an increased voltage across thecapacitor, electrical charges flow into the capacitor until thecapacitor is charged to the increased voltage. Similarly, when the powersource applies a decreased voltage the capacitor, electrical chargesflow out of the capacitor until the capacitor is discharged to thedecreased voltage. The amount of time it takes for the capacitor tocharge or discharge is dependent on the change in voltage applied andthe capacitance of the capacitor. Thus if the capacitance is unknown, itcan calculated from the charge or discharge time and the change involtage applied. A person touching or coming close to a capacitive touchsensor can change the sensor's effective capacitance by combining theperson's capacitance with the capacitance of the capacitive touchsensor. This change in effective capacitance can be detected by a changein the charge or discharge times.

Most common capacitive touch sensors, such as those used in cell phonesand ATMs are made on inflexible substrates several millimeters thick andprotected by glass. Thin film capacitive touch sensors are known, suchas those taught in U.S. Pat. No. 6,819,316 “Flexible capacitive touchsensor.” However, thin film capacitive touch sensors not used as muchdue to several technical challenges, including a “two-sided” effect thatmakes thin film capacitive touch sensors sensitive to touch on bothsides of the sensor.

A recent proliferation of inexpensive computer processors and logicdevices has influenced games, toys, books, and the like. For example,some kinds of games, toys, and books use embedded sensors in conjunctionwith control logic coupled to audio and/or visual input/output logic toenrich the interactive experience provided by the game, toy, book, orthe like. An example is a book or card (e.g., greeting card) that cansense the identity of an open page or card and provide auditory feedbackto the reader relevant to the content of the open page or card.

Many conventional stand-alone computer games provide a visual display ofgame activity through an electronic display system such as a pixilatedflat panel display. Such displays lack the three-dimensional characterand physical interaction inherent in typical board-based games. Forexample, a conventional board game may use of one or more movableplaying pieces integral to the action of the game. Conversely,conventional board games often lack the audio and/or visual interactionand computerized game play offered by computer games.

A number of prior art patents have described games (e.g., board games),toys, books, and cards that utilize computers and sensors to detecthuman interaction with elements of the board games, toys, books, andcards. The following represents a list of known related art:

Date of Reference: Issued to: Issue/Publication: U.S. Pat. No. 5,645,432Jessop Jul. 8, 1997 U.S. Pat. No. 5,538,430 Smith et al. Jul. 23, 1996U.S. Pat. No. 4,299,041 Wilson Nov. 10, 1981 U.S. Pat. No. 6,955,603Jeffway, Jr. et al Oct. 18, 2005 U.S. Pat. No. 6,168,158 Bulsink Jan. 2,2001 U.S. Pat. No. 5,853,327 Gilboa Dec. 29, 1998 U.S. Pat. No.5,413,518 Lin May 9, 1995 U.S. Pat. No. 5,188,368 Ryan Feb. 23, 1993U.S. Pat. No. 5,129,654 Bogner Jul. 14, 1992

The teachings of each of the above-listed citations (which does notitself incorporate essential material by reference) are hereinincorporated by reference. None of the above inventions and patents,taken either singularly or in combination, is seen to describe anembodiment or embodiments of the instant invention described below andclaimed herein.

For example, U.S. Pat. No. 5,853,327 “Computerized Game Board” describesa system that automatically senses the position of toy figures relativeto a game board and thereby supplies input to a computerized gamesystem. The system requires that each game piece to be sensedincorporate a transponder, which receives an excitatory electromagneticsignal from a signal generator and produces a response signal that isdetected by one or more sensors embedded in the game board. Thecomplexity and cost of such a system make it impractical for low-costgames and toys.

U.S. Pat. No. 5,129,654 “Electronic Game Apparatus,” U.S. Pat. No.5,188,368 “Electronic Game Apparatus,” and U.S. Pat. No. 6,168,158“Device for Detecting Playing Pieces on a Board” all describe systemsusing resonance frequency sensing to determine the position and/oridentity of a game piece. Each system requires a resonator circuitcoupled with some particular feature of each unique game piece, whichincreases the complexity and cost of the system while reducing theflexibility of use.

U.S. Pat. No. 5,413,518 “Proximity Responsive Toy” describes anotherexample of a toy incorporating automatic sensing that utilizes acapacitive sensor coupled to a high frequency oscillator, whereby thefrequency of the oscillator is determined in part by the proximity ofany conductive object (such as a human hand) to the capacitive sensor.This system has the disadvantages of requiring specialized electroniccircuitry that may limit the number of sensors that can besimultaneously deployed.

U.S. Pat. No. 6,955,603 “Interactive Gaming Device Capable of PerceivingUser Movement” describes another approach to sensing player interactionby using a series of light emitters and light detectors to measure theintensity of light reflected from a player's hand or other body part.Such a system requires numerous expensive light emitters and lightdetectors, in particular for increasing the spatial sensitivity fordetection.

U.S. Pat. No. 5,645,432 “Toy or Educational Device” describes a toy oreducational device that includes front and back covers, a spine, aplurality of pages, a plurality of pressure sensors mounted in the frontand back covers and a sound generator connected to the pressure sensors.The pressure sensors are responsive to the application of pressure to analigned location of a page overlying the corresponding cover foractuating the sound generator to generate sounds associated with boththe location of the sensor which is depressed and the page to whichpressure is applied.

U.S. Pat. No. 5,538,430 “Self-reading Child's Book” describes aself-reading electronic child's book that displays a sequence ofindicia, such as words, and has under each indicia a visual indicatorsuch as a light-emitting diode with the visual indicators beingautomatically illuminated in sequence as the child touches a switchassociated with each light-emitting diode to sequentially drive a voicesynthesizer that audibilizes the indicia or word associated with thelight and switch that was activated.

U.S. Pat. No. 4,299,041 “Animated Device” describes a device in the formof a greeting card, display card, or the like, for producing a visualand/or a sound effect that includes a panel member or the like ontowhich is applied pictorial and/or printed matter in association with aneffects generator, an electronic circuit mounted on the panel member butnot visible to the reader of the matter but to which the effectsgenerator is connected, and an activator on the panel member, which,when actuated, causes triggering of the electronic circuit to energizethe effects generator.

Each of the prior art patents included above describes a game, toy,book, and/or card that requires expensive components or manufacturingtechniques and/or exhibits limited functionality. As will be describedbelow, embodiments of the present invention overcome these limitations

SUMMARY AND ADVANTAGES

Embodiments of a touch sensitive sensor system are described herein,comprising a capacitive touch sensor layer, a separation layer adjacentthe capacitive touch sensor layer, and a conductive ground plane layeradjacent the separation layer to shield a backside of the capacitivetouch sensor layer. An alternate embodiment is a touch sensitive sensorsystem comprising a capacitive touch sensor layer and separation layerto create an air gap layer adjacent the capacitive touch sensor layer toshield a backside of the capacitive touch sensor layer.

The system and method for thin capacitive touch sensors of the presentinvention present numerous advantages, including: (1) inexpensive andsimple construction; (2) substantially one-sided triggering of thecapacitive touch sensors in particular for hand-held devices; (3) thinconstruction; (4) touch sensing application to games, board games, toys,books, and greeting cards; and (5) integration of printed art on a layeror substrate with the capacitive touch sensors.

Additional advantages of the invention will be set forth in part in thedescription which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. Theadvantages of the invention may be realized and attained by means of theinstrumentalities and combinations particularly pointed out in theappended claims. Further benefits and advantages of the embodiments ofthe invention will become apparent from consideration of the followingdetailed description given with reference to the accompanying drawings,which specify and show preferred embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and constitute apart of this specification, illustrate one or more embodiments of thepresent invention and, together with the detailed description, serve toexplain the principles and implementations of the invention.

FIGS. 1-4 illustrate several embodiments of thin film capacitive touchsensors with different fill patterns.

FIGS. 5 and 6 illustrate methods of combining thin film capacitive touchsensors with printed art.

FIG. 7 illustrates a one-sided thin film capacitive touch sensor with aconductive ground plane layer.

FIG. 8 illustrates a one-sided thin film capacitive touch sensor with analternative ground plane configuration.

FIG. 9 shows another view of the one-sided thin film capacitive touchsensor of FIG. 8.

FIG. 10 is an exploded view of a book constructed with thin filmcapacitive touch sensors and a conductive ground plane layer.

FIG. 11 illustrates book construction with thin film capacitive touchsensors of the front and back covers and one or more foil ground planes.

FIG. 12 illustrates board game construction with thin film capacitivetouch sensors and a conductive ground plane layer.

FIG. 13 illustrates board game construction of an alternate embodiment.

FIG. 14 illustrates an example of a one room doll house.

FIG. 15 illustrates doll house construction with thin film capacitivetouch sensors and a conductive ground plane layer.

FIG. 16A illustrates greeting card construction with thin filmcapacitive touch sensors and a conductive ground plane layer.

FIG. 16B illustrates greeting card construction of an alternateembodiment.

FIG. 17A illustrates guitar construction with thin film capacitive touchsensors and one or more conductive ground plane layers.

FIG. 17B illustrates guitar construction of an alternate embodiment.

FIG. 18A illustrates drum set construction with thin film capacitivetouch sensors and a conductive ground plane layer.

FIG. 18B illustrates drum set construction of an alternate embodiment.

FIG. 19A illustrates a side view of a capacitive sensor with air gaplayers for shielding.

FIG. 19B illustrates a side view of a capacitive sensor of an alternateembodiment with air gap layers for shielding.

FIG. 19C illustrates a side view of a capacitive sensor of an alternateembodiment with separating material for shielding.

FIG. 20 illustrates a side view of a capacitive sensor mounted oncorrugated cardboard for shielding.

FIG. 21 illustrates book construction with thin film capacitive touchsensors and an air gap layer.

FIG. 22 Illustrates board game construction with thin film capacitivetouch sensors and an air gap layer.

FIG. 23 illustrates doll house construction with thin film capacitivetouch sensors and an air gap layer.

FIG. 24A illustrates drum set construction with thin film capacitivetouch sensors and an air gap layer.

FIG. 24B illustrates drum set construction of an alternate embodiment.

FIG. 25A illustrates greeting card construction with thin filmcapacitive touch sensors and an air gap layer.

FIGS. 25B, 25C & 25D illustrate greeting card construction of analternate embodiment with a pop-up with thin film capacitive touchsensors and an air gap layer.

FIG. 26A illustrates a guitar construction method with thin filmcapacitive touch sensors and an air gap layer.

FIG. 26B. illustrates a guitar construction method of an alternateembodiment.

REFERENCE NUMBERS USED IN DRAWINGS

In the drawings, similar reference characters denote similar elementsthroughout the several figures. With regard to the reference numeralsused, the following numbering is used throughout the various drawingfigures:

-   -   10 thin film capacitive touch sensor    -   12 capacitive element    -   14 thin film substrate    -   16 interconnect    -   20 50% fill pattern capacitive touch sensor    -   22 50% fill pattern capacitive element    -   30 35% fill pattern capacitive touch sensor    -   32 35% fill pattern capacitive element    -   34 thin film capacitive touch sensor    -   36 capacitive field    -   42 printed art layer    -   44 capacitive touch sensor layer    -   46 capacitive elements    -   48 thin film substrate    -   52 printed art layer    -   54 capacitive touch sensor layer    -   56 capacitive elements    -   58 thin film substrate    -   60 one-sided thin film capacitive touch sensor    -   62 conductive ground plane layer    -   64 capacitive touch sensor layer    -   66 separation layer    -   70 one-sided thin film capacitive touch sensor    -   71 capacitive elements    -   72 conductive ground plane layer    -   74 capacitive touch sensor layer    -   76 separation layer    -   78 thin film    -   80 electronics    -   90 book    -   91 pages    -   92 front cover    -   94 back cover    -   95 capacitive touch sensor layer    -   96 conductive ground plane layer    -   98 electronics package    -   100 book    -   102 thin film capacitive touch sensors    -   104 back cover    -   105 inside surface    -   106 conductive ground plane layers    -   107 outside surface    -   108 front cover    -   110 inside surface    -   112 outside surface    -   114 electronics package    -   120 board game    -   122 printed art layer    -   124 capacitive touch sensor layer    -   126 separation layer    -   128 conductive ground plane layer    -   129 game board back wrap    -   130 interactive board game    -   132 printed art layer    -   134 thin film capacitive touch sensors    -   136 separation layer    -   138 conductive ground plane layer    -   140 doll house    -   142 capacitive touch sensor layer    -   144 conductive ground plane layer    -   145 floor    -   146 walls    -   148 separation layer    -   149 printed outside wall decorative layer    -   150 greeting card    -   152 printed art layer    -   154 capacitive touch sensor layer    -   155 separation layer    -   156 conductive ground plane layer    -   157 card backing layer    -   158 electronics package    -   160 greeting card    -   162 printed art layer    -   164 capacitive touch sensor layer    -   165 separation layer    -   166 conductive ground plane layer    -   167 card backing layer    -   168 electronics package    -   170 one-sided thin film capacitive touch sensor    -   172 capacitive touch sensor layer    -   174 separating base    -   176 air gap layer    -   180 one-sided thin film capacitive touch sensor    -   182 capacitive touch sensor layer    -   184 separating base    -   186 air gap layer    -   190 one-sided thin film capacitive touch sensor    -   192 capacitive touch sensor layer    -   194 thick separating material    -   200 one-sided thin film capacitive touch sensor    -   202 capacitive touch sensor layer    -   204 corrugated structure    -   206 air gap layer    -   220 capacitive guitar    -   222 guitar body    -   224 neck conductive ground plane layer    -   226 neck housing    -   228 guitar neck    -   230 body conductive ground plane layer    -   232 body separation layer    -   234 printed art layer    -   236 capacitive touch sensor layer    -   238 electronics package    -   239 speaker    -   240 capacitive drum set    -   242 printed art layer    -   244 capacitive touch sensor layer    -   246 plastic drum platform    -   248 conductive ground plane layer    -   250 electronics package    -   252 speaker    -   260 book    -   261 pages    -   262 front cover    -   264 back cover    -   265 capacitive touch sensor layer    -   266 lattice structure    -   268 lattice backing    -   269 electronics package    -   270 interactive board game    -   272 printed art layer    -   274 capacitive touch sensor layer    -   276 separating base    -   280 doll house    -   282 capacitive touch sensor layers    -   284 separation base    -   285 floor    -   286 interior walls    -   288 separation layer    -   289 outside decorative walls    -   290 capacitive drum set    -   292 printed art layer    -   294 capacitive touch sensor layer    -   296 plastic drum platform    -   298 separation base    -   300 electronics package    -   302 speaker    -   310 greeting card    -   312 printed art layer    -   314 capacitive touch sensor layer    -   316 separation base    -   317 card backing layer    -   318 electronics package    -   320 greeting card    -   322 pop-up    -   324 card top    -   326 card bottom    -   328 air gap layer    -   330 printed art layer    -   332 capacitive touch sensor layer    -   334 electronics package    -   340 capacitive guitar    -   342 guitar body    -   344 air gap layer    -   346 neck housing    -   348 guitar neck    -   350 conductive ground plane layer    -   352 body separation layer    -   354 printed art layer    -   356 capacitive touch sensor layer    -   358 electronics package    -   359 speaker

DETAILED DESCRIPTION

Before beginning a detailed description of the subject invention,mention of the following is in order. When appropriate, like referencematerials and characters are used to designate identical, corresponding,or similar components in differing figure drawings. The figure drawingsassociated with this disclosure typically are not drawn with dimensionalaccuracy to scale, i.e., such drawings have been drafted with a focus onclarity of viewing and understanding rather than dimensional accuracy.

In the interest of clarity, not all of the routine features of theimplementations described herein are shown and described. It will, ofcourse, be appreciated that in the development of any such actualimplementation, numerous implementation-specific decisions must be madein order to achieve the developer's specific goals, such as compliancewith application- and business-related constraints, and that thesespecific goals will vary from one implementation to another and from onedeveloper to another. Moreover, it will be appreciated that such adevelopment effort might be complex and time-consuming, but wouldnevertheless be a routine undertaking of engineering for those ofordinary skill in the art having the benefit of this disclosure.

FIGS. 1-26B illustrate several embodiments of thin film capacitive touchsensors and several embodiments of applications thereof. FIGS. 1-8generally describe the construction of two-sided thin film capacitivetouch sensors. FIGS. 7-18B generally describe one-sided thin filmcapacitive touch sensors with conductive ground plane layers. FIGS.19A-26B generally describe one-sided thin film capacitive touch sensorswith air gap layers. The relative low cost and simplicity/elegance ofthese thin film capacitive touch sensors enable games (e.g., boardgames), toys (e.g., musical instruments such as guitars and drums),books, and greeting cards to include touch sensitive functionality. Thegames, toys, books, and greeting cards described herein includeone-sided thin film capacitive touch sensors including both conductiveground plane layers and air gap layers.

Many existing sample capacitive design kits available from manufacturersuse printed circuit boards to create and connect thin film capacitivetouch sensors. This approach is too expensive and cumbersome for mostlow-cost (e.g., game, toy, book, and greeting card, among others)applications. A low-cost alternative is to manufacture thin filmcapacitive touch sensors (thin compared to printed circuit boards). Onemethod of manufacturing thin film capacitive touch sensors is to printthe elements of the capacitors with conductive ink onto a thin filmsubstrate using a screen printing technique. The thin film substrate maybe a sheet of material like plastic (e.g., polyester) or paper. Inaddition to being lower cost than a printed circuit board, thin filmsubstrates such as polyester or paper are more flexible.

FIGS. 1-4 illustrate several embodiments of thin film capacitive touchsensors with different fill patterns. FIG. 1 shows a thin filmcapacitive touch sensor 10 with a solid fill pattern. The thin filmcapacitive touch sensor 10 has a thin film substrate 14 and a capacitiveelement 12. The capacitive element 12 is made of conductive inkdeposited without porosity on the thin film substrate 14, giving it asolid fill pattern. In this embodiment, the conductive ink is depositedusing a screen printing technique, but in other embodiments, othertechniques may be used. The thin film capacitive touch sensor 10 alsohas an interconnect 16, configured to electrically connect thecapacitive element 12 to circuits outside of the thin film capacitivetouch sensor 10. In this embodiment, the interconnect 16 is alsoconductive ink deposed on the thin film substrate 14. Capacitiveelements and interconnects are collectively referred to herein as“conductive pathways.”

The conductive ink used generally includes a polymer and a metal and/orcarbon conductive material. For example, the polymer may includepowdered and/or flaked silver, gold, copper, nickel, and/or aluminum. Insome embodiments, the conductive pathways range from less than 100 Ohmsto 8K Ohms resistance, depending on their material composition andconfiguration. Conductive ink with less conductive material may be lessexpensive, but may exhibit greater resistivity. Conductive ink with agreater amount of conductive material may be more expensive, but mayexhibit decreased resistivity.

The cost of capacitive touch sensors may be mitigated by substitutingthe capacitive element 12 with the solid fill pattern shown in FIG. 1with a capacitive element having a partial fill pattern, resulting in apartial fill pattern capacitive touch sensor. The partial fill patterncapacitive element is porous, resulting in an area of thin filmsubstrate under the partial fill pattern capacitive element having lessthan complete conductive ink coverage. However, the partial fill patterncapacitive element is continuous, so that electrical charges can flow toall parts of the element.

As examples of partial fill pattern capacitive touch sensors, FIG. 2shows a 50% fill pattern capacitive touch sensor 20 and FIG. 3 shows a35% fill pattern capacitive touch sensor 30. In FIG. 2, the 50% fillpattern capacitive touch sensor 20 has a 50% fill pattern capacitiveelement 22, meaning only 50% of a thin film substrate 14 under the 50%fill pattern capacitive element 22 is covered by conductive material. InFIG. 3, the 35% fill pattern capacitive touch sensor 30 has a 35% fillpattern capacitive element 32, meaning only 35% of a thin film substrate14 under the 35% fill pattern capacitive element 32 is covered byconductive material. As the percentage of fill pattern decreases, thecapacitance of the capacitive touch sensor is reduced, but the areacovered by the capacitive touch sensor remains the same. For manyapplications that detect human finger touches, 35% and greater fill maydecrease the cost of the capacitive touch sensor substantially withoutsuffering significant performance loss. Thus a capacitive element canremain a large target for a user to touch, but with reduced conductivematerial.

In the embodiments shown in FIGS. 1-3, the partial fill pattern shown isa rectilinear grid of crisscrossed horizontal and vertical linesintersecting at right angles. However, other partial fill patterns maybe used, such as a regular pattern of small circular pores. Forconvenience, herein “grid” shall mean any partial fill pattern.

FIG. 4 shows a side view of a thin film capacitive touch sensor 34 likethose discussed regarding FIGS. 1-3. When charged, a capacitive field 36extends from the front and back of the thin film capacitive touch sensor34. The capacitive field 36 is an electrical field that will interactwith nearby conductive objects, such as a human finger, changing theeffective capacitance of the thin film capacitive touch sensor 34. Thethin film capacitive touch sensor 34 can be said to be “two-sided,”since interaction with the capacitive field 36 on either the front sideor back side can be detected via the change in effective capacitance.

Alternately, instead of screen printed conductive ink, one or more ofthe conductive pathways may be formed from thin copper or other metallayers. For example, one or more of the conductive pathways may beformed from a thin copper sheet that is photo-lithographically patternedand etched to form one or more of the conductive pathways, i.e. thecapacitive element and/or related interconnects. Capacitive elementswith partial fill patterns may be etched from thin metal as well. Thecopper conductive pathways may be laminated to a flexible substratelayer. Accordingly, both the copper and conductive ink conductivepathway embodiments, or a combination thereof, may form at least part ofa flexible circuit (e.g., a “flex” circuit).

In some embodiments, any additional electronics that couple to the oneor more capacitive elements and related interconnects may be at least inpart be included on the same flexible substrate as the one or more thinfilm capacitive touch sensors. Alternately, at least some of theadditional electronics may be included on a separate substrate. Forexample, at least some of the electronics may be included on a separateprinted circuit board. Multiple circuits on multiple substrates may beelectrically coupled together with any electrical coupling devicesand/or methods known in the art.

FIGS. 5 and 6 illustrate methods of combining thin film capacitive touchsensors with printed art. FIG. 5 illustrates a first method of combiningthin film capacitive touch sensors with printed art. A capacitive touchsensor layer 44 is coupled to a printed art layer 42 by lamination,gluing or other process. This capacitive touch sensor layer 44 comprisesone or more (three in the embodiment shown) capacitive elements 46deposed on a thin film substrate 48 (e.g. paper or plastic), forming oneor more thin film capacitive touch sensors, similar in construction tothose described in the discussion regarding FIGS. 1-4. In thisembodiment, the capacitive elements 46 are conductive ink deposed on thethin film substrate 48 using a screen printing process. In otherembodiments, the capacitive elements 46 may be made with lithography outof metal foil, or some other method.

FIG. 6 illustrates a second method of combining thin film capacitivetouch sensors with printed art. Here, a printed art layer 52 comprisesart printed directly onto a thin film substrate 58. One or morecapacitive elements 56 are deposed onto the same thin film substrate 58as well, forming a capacitive touch sensor layer 54. In someembodiments, an opaque layer of non-conductive ink may be printed on theprinted art layer 52 over the art and the capacitive elements 56 printedover the opaque layer. This opaque layer substantially prevents theconductive pathways and/or product supporting structure from showingthrough the thin film substrate 58. In other embodiments, the capacitiveelements 56 are printed directly over the printed art layer 52 withoutan opaque layer.

FIGS. 7-18B illustrate embodiments of one-sided thin film capacitivetouch sensors with conductive ground plane layers to substantiallymitigate the two-sided functionality of the thin film capacitive touchsensors described by the discussion regarding FIGS. 1-6. In particularfor games, toys, books, and greeting cards that may be handheld,one-sided thin film capacitive touch sensors may improve the abilitywith which a user may properly interact with the games, toys, books, andgreeting cards.

FIG. 7 illustrates a one-sided thin film capacitive touch sensor 60 witha conductive ground plane layer 62. The one-sided thin film capacitivetouch sensor 60 comprises a capacitive touch sensor layer 64 separatedfrom the conductive ground plane layer 62 with a separation layer 66.The capacitive touch sensor layer 64 is a two-sided thin film capacitivetouch sensor as described in the discussion regarding FIGS. 1-4. In thisembodiment, the separation layer 66 is a thin sheet of dielectricmaterial like paper or plastic. In one embodiment, the conductive groundplane layer 62 is constructed by mounting a very thin sheet ofconductive material such as aluminum foil or screen printed conductiveink on the backside of the separation layer 66. The separation betweenthe capacitive touch sensor layer 64 and the conductive ground planelayer 62 is a minimum of 0.5 mm. Any separation less than 0.5 mm causesbase capacitance of the capacitive touch sensor layer 64 to increasedramatically, so much so that any touch by a human finger will notchange the effective capacitance of the capacitive touch sensor layer64, rendering such touches undetectable. Any separation less than 0.5 mmmay cause the one-sided thin film capacitive touch sensor 60 toexperience large changes in base capacitance when the capacitive touchsensor layer 64 experiences mechanical bending. Simply flexing theone-sided thin film capacitive touch sensor 60 may lead to fluctuationsin effective capacitance larger than those typically seen when one-sidedthin film capacitive touch sensor 60 is touched by a human finger,degrading the touch sensitivity of the one-sided thin film capacitivetouch sensor 60.

FIG. 8 illustrates a one-sided thin film capacitive touch sensor 70 withan alternative ground plane configuration. The one-sided thin filmcapacitive touch sensor 70 has one or more capacitive elements 71 (notvisible this view, see FIG. 9) deposed on a thin film 78 to form acapacitive touch sensor layer 74 and a conductive ground plane layer 72deposed on the same thin film 78, the thin film 78 wrapped around aseparation layer 76. In this embodiment, the separation layer 76 is athin sheet of dielectric material like paper or plastic.

FIG. 9 shows another view of the one-sided thin film capacitive touchsensor 70 of FIG. 8, showing the capacitive elements 71 and conductiveground plane layer 72 deposed on the same thin film 78, the thin film 78laid flat, but configured to be wrapped around separation layer 76 (seeFIG. 9C with arrow showing wrapping action). The conductive ground planelayer 72 may be a grid or solid fill pattern, as described aboveregarding FIGS. 1-4. In some embodiments, capacitive elements 71 and theconductive ground plane layer 72 may be formed from the same conductivematerial (e.g., conductive ink) and substantially simultaneously (e.g.,from the same patterned printing screen). Also shown are electronics 80for measuring the effective capacitance of the one-sided thin filmcapacitive touch sensor 70.

FIG. 10 is an exploded view of a book 90 constructed with thin filmcapacitive touch sensors and a conductive ground plane layer. The book90 has pages 91, a front cover 92 and a back cover 94, a capacitivetouch sensor layer 95 with one or more thin film capacitive touchsensors, a conductive ground plane layer 96, and a lattice backing 98.The capacitive touch sensor layer 95 is deposed on a side of the backcover 94 facing the pages 91 and the conductive ground plane layer 96 isdeposed on the other side of the back cover 94. An electronics package99 is attached to the back cover 94. The conductive ground plane layer96 in or adjacent the back cover 94 will lower the sensitivity of thethin film capacitive touch sensors to a user's hands and lower thelikelihood of false and/or unintentional capacitive sensor triggeringwhen, for example, the book is held.

FIG. 11 is an exploded view of a book 100 constructed with thin filmcapacitive touch sensors 102. The book 100 has a back cover 104 with anoutside surface 107 and an inside surface 105. The book 100 has a frontcover 108 with an outside surface 112 and an inside surface 110. Thethin film capacitive touch sensors 102 are deposed on inside surfaces105 and 110. Conductive ground plane layers 106 are deposed on outsidesurfaces 107 and 112. An electronics package 114 is attached to the backcover 104 and electrically coupled to the thin film capacitive touchsensors 102 and the conductive ground plane layers 106. In someembodiments, the front and/or back covers 104 and 108 typically includea paper board that is approximately 2.0 mm thick. This separationexceeds the 0.5 mm separation between the capacitive touch sensor layerand the conductive ground plane layer required for good one-sided sensorcharacteristics. Since covers are a feature generally included with thebook, there is no marginal expense of adding additional layers toachieve good one sided sensor operation.

FIG. 12 illustrates a interactive board game 120 embodiment. Theinteractive board game 120 includes a printed art layer 122, acapacitive touch sensor layer 124, a separation layer 126 (e.g. chipboard), a conductive ground plane layer 128 (e.g., a metal foil and/ormetal foil paper), and a game board back wrap 129. The capacitive touchsensor layer 124 is separated from the conductive ground plane layer 128by the separation layer's 126 approximately 2.0 mm thickness. Thisprovides more than the 0.5 mm separation between the capacitive touchsensor layer 124 and the conductive ground plane layer 128 required forgood one-sided sensor characteristics.

FIG. 13 illustrates a board game 130 embodiment constructed with a thinfilm capacitive touch sensors 134 printed on the backside (underside) ofa printed art layer 132. Similar to the configuration of layersillustrated by FIG. 12, the thin film capacitive touch sensors 134 maybe separated from a conductive ground plane layer 138 by a separationlayer 136 (such as a chip board) that is approximately 2.0 mm thick.This provides more than the 0.5 mm separation required for goodone-sided sensor characteristics.

FIG. 14 illustrates a one room doll house 140 embodiment. FIG. 15 showsan exploded view of the details of the doll house 140 constructionincluding a capacitive touch sensor layer 142 and a conductive groundplane layer 144. The capacitive touch sensor layer 142 may be laminatedinto floor 145 and walls 146 of the doll house 140. The capacitive touchsensor layer 142 may alternately be glued to the floor 145 and walls 146of the doll house. The conductive ground plane layer 144 may belaminated to the outside of the doll house 140 to block unwantedcapacitive sensitivity. In this embodiment, the capacitive touch sensorlayer 142 are separated from the conductive ground plane layer 144 witha separation layer 148 (e.g., chip board and/or plastic) that isapproximately 1.0 mm to 2.0 mm thick. This provides more than the 0.5 mmseparation required for good one-sided sensor characteristics. A printedoutside wall decorative layer 149 covers and protects the conductiveground plane layer 144.

FIG. 16A illustrates a greeting card 150. The greeting card 150 includesa printed art layer 152, a capacitive touch sensor layer 154, aseparation layer 155, a conductive ground plane layer 156, a cardbacking layer 157, and an electronics package 158. The separation layer155 may be an approximately 2.0 mm thick chip board and the conductiveground plane layer 156 may be a metal foil and/or metal foil paper. Theshielding of the capacitive touch sensor layer 154 is an importantfeature for the greeting card to function properly as a greeting card ishand held when it is operated. The inclusion of the conductive groundplane layer 156 will mitigate false and/or unintentional triggering ofthin film capacitive touch sensors in the capacitive touch sensor layer154 from the back side of the greeting card 150 when the greeting card150 is being held.

FIG. 16B illustrates a greeting card 160 alternate embodiment. Thegreeting card 160 includes a printed art layer 162, a capacitive touchsensor layer 164, a separation layer 165, a conductive ground planelayer 166, a card backing layer 167, and an electronics package 168. Inthis embodiment, the capacitive touch sensor layer 164 is integrallyformed with the printed art layer 162. The separation layer 165 may bean approximately 2.0 mm thick chip board and the conductive ground planelayer 166 may be a metal foil and/or metal foil paper. The shielding ofthe capacitive touch sensor layer 164 is an important feature for thegreeting card to function properly as a greeting card is hand held whenit is operated. The inclusion of the conductive ground plane layer 166will mitigate false and/or unintentional triggering of thin filmcapacitive touch sensors in the capacitive touch sensor layer 164 fromthe back side of the greeting card 160 when the greeting card 160 isbeing held.

FIG. 17A illustrates a capacitive guitar 220 embodiment constructionusing a separate printed sensor layer beneath the printed art layer. Thecapacitive guitar 220 comprises a guitar body 222, a guitar neck 228, aneck housing 226, a neck conductive ground plane layer 224, a bodyconductive ground plane layer 230, a body separation layer 232, aprinted art layer 234, capacitive touch sensor layer 236, an electronicspackage 238 and a speaker 239. In this embodiment, two separateconductive ground plane layers are used because of the product'sphysical design. The guitar body 222 provides a separation layer for aneck conductive ground plane layer 224. This is possible because of theneck housing 226 covering the back of the guitar neck 228. The bodyconductive ground plane layer 230 doesn't have a separate housingcovering the back of the entire guitar body 222, so it is mounted on thetop of the guitar body 222 with body separation layer 232 between it andthe capacitive touch sensor layer 236. In general, the guitar isconstructed substantially the same as the book, game board, and greetingcard embodiments described above.

Alternately, as illustrated by FIG. 17B, the capacitive touch sensorlayer 236 combined into the printed art layer 234, the combined layerwith both full color printing on the front side and screen printedcapacitive elements on the backside or underside.

FIGS. 18A and 18B illustrate a capacitive drum set 240. The capacitivedrum set 240 has a printed art layer 242, a capacitive touch sensorlayer 244, a plastic drum platform 246, a conductive ground plane layer248, an electronics package 250, and a speaker 252. In general, the drumset is constructed substantially the same as the book, game board,greeting card, and guitar embodiments described above. Alternately, asillustrated by FIG. 18B, the capacitive touch sensor layer 244 iscombined in the printed art layer 242 with both full color printing onthe front side and the screen printed capacitive elements on thebackside or underside. For both embodiments, the plastic drum platformmay serve as the separation layer between the capacitive touch sensorlayer 244 and the conductive ground plane layer 248.

FIGS. 19A-26B illustrate embodiments including an air gap layer tosubstantially mitigate the two-sided functionality of the thin filmcapacitive touch sensors described by FIGS. 1-8 while maintaining thesubstantially low cost and simple construction. In particular for games,toys, books, and greeting cards that may be handheld, the one-sidedfunctionality of the thin film capacitive touch sensors may improve theability with which a user may properly interact with the games, toys,books, and greeting cards.

As an alternate approach to including a conductive ground plane layershield to form a substantially one-sided capacitive sensor, otherembodiments use materials with very low dielectric constants as a shieldfor one side of the capacitive sensor. More specifically, one veryinexpensive material with a very low dielectric constant is air. Theinclusion of an air gap layer will lower the capacitive sensitivity onthe air gap layer side of the capacitive sensor. Nevertheless, acapacitive field may still be triggered by proximity though the airdepending on the configuration of the capacitive sensor. Accordingly,one-sided thin film capacitive touch sensors with an air gap layershould be tested for any potential application to determine theirsuitability. For example, there is a relationship between the size/areaof a touch capacitive sensor and its proximity sensitivity through air.Generally, larger capacitive touch sensors are more sensitive and mayrequire a thicker air-gap for proper shielding. As a guideline, the airgap layer should be at least the thickness of any overlay material ontop of the capacitive elements. For example, a configuration thatincludes a thin film capacitive touch sensor 2 mil thick (capacitiveelements printed in conductive ink on bottom), an printed art layer 10mil thick and a 5 mil layer of glue totals an overlay of 17 mil over thecapacitive elements. This would suggest an air gap layer of at least a17 mil (˜0.5 mm). For capacitive elements less than 2 square inches inarea, an air gap layer of five times the overlay thickness have provento be sufficient.

FIG. 19A shows a side view of one-sided thin film capacitive touchsensor 170 including an air gap layer 176 for shielding. The one-sidedthin film capacitive touch sensor 170 includes a capacitive touch sensorlayer 172 mounted to a separating base 174. The separating base 174 hasa molded or cut pattern to create the air gap layer 176 on a side of theseparating base 174 opposite the capacitive touch sensor layer 172. Theseparating base 174 prevents foreign objects, such as a human finger,from entering the air gap layer 176 and changing the effectivecapacitance of a sensor in the capacitive touch sensor layer 172. Theair gap layer 176 mitigates sensitivity to touch from the bottom, asexplained above. In this embodiment the separating base 174 has alattice structure, but in other embodiments, structures with othergeometries, such as a corrugation structure, may be used to create theair gap layer 176.

FIG. 19B shows a side view of one-sided thin film capacitive touchsensor 180 including an air gap layer 186 for shielding. The one-sidedthin film capacitive touch sensor 180 includes a capacitive touch sensorlayer 182 mounted to a separating base 184. The separating base 184 hasa molded or cut pattern to create the air gap layer 186 on a side of theseparating base 184 closest to the capacitive touch sensor layer 182.The separating base 184 prevents foreign objects, such as a humanfinger, from entering the air gap layer 186 and changing the effectivecapacitance of a sensor in the capacitive touch sensor layer 182. Theair gap layer 186 mitigates sensitivity to touch from the bottom. Inthis embodiment the separating base 184 has a lattice structure, but inother embodiments, structures with other geometries, such as acorrugation structure, may be used to create the air gap layer 186.

FIG. 19C shows a side view of a one-sided thin film capacitive touchsensor 190 including a thick separating material 194. The one-sided thinfilm capacitive touch sensor 190 includes a capacitive touch sensorlayer 192 mounted to the thick separating material 194. The thickseparating material 194 is a non-conducting material such as plastic orcardboard. The one-sided thin film capacitive touch sensor 190 reducesor eliminates sensitivity to touches on the back side of the capacitivetouch sensor layer 192 with thick separating material 194. The thickseparating material 194 forces such touches further from the back sideof the capacitive touch sensor layer 192 and accordingly reduces changeto effective capacitance of the capacitive touch sensor layer 192 duringsuch touches.

FIG. 20 shows a one-sided thin film capacitive touch sensor 200 with airgap layer 206 provided by a corrugated structure 204, such as corrugatedcardboard or similar materials. The thin film capacitive touch sensor200 has a capacitive touch sensor layer 202 mounted on the corrugatedstructure 204, which mitigates sensitivity to touches on a side of thecapacitive touch sensor layer 202 nearest the corrugated structure 204(i.e. the back side) due to diminished strength of a capacitive field208 generated by the capacitive touch sensor layer 202 after passingthrough the corrugated structure 204. Such corrugated structures, inparticular with corrugated cardboard and the like, are inexpensiveconstruction materials common to games and toys.

Accordingly, these air gap layer embodiments of one-sided thin filmcapacitive touch sensors may be easily and inexpensively integrated intogames, toys, and the like to add interactive and other computer-basedfeatures. For example, as will be explained in more detail below, aconductive ground plane layer may be replaced by a lattice structure orthe like to provide substantially one-sided functionality for capacitivetouch sensors.

FIG. 21 is an exploded view of a book 260 constructed with thin filmcapacitive touch sensors and a lattice structure to provide an air gaplayer. The book 260 has pages 261, front cover 262 and a back cover 264,a capacitive touch sensor layer 265 with one or more thin filmcapacitive touch sensors, a lattice structure 266, and a lattice backing268. The capacitive touch sensor layer 265 is deposed on a side of theback cover 264 facing the pages 261 and the lattice structure 266 isdeposed on the other side of the back cover 264. An electronics package269 is attached to the front cover 262. As illustrated, the latticestructure 266 is provided between the capacitive touch sensor layer 265and the lattice backing 268 to form an air gap layer while providingmechanical support to the lattice backing 268. The air gap layer in oradjacent the back cover 264 will lower the sensitivity of the thin filmcapacitive touch sensors to a user's hands and lower the likelihood offalse and/or unintentional capacitive sensor triggering when, forexample, the book is held. Said differently, the air gap layer increasesthe one-sided functionality of the thin film capacitive touch sensors.

FIG. 22 illustrates a interactive board game 270 embodiment with alattice structure to provide an air gap layer. The interactive boardgame 270 includes a printed art layer 272, a capacitive touch sensorlayer 274, and a separating base 276. In this embodiment, a plasticboard is used as the separating base 276. The separating base 276 mayinclude a molded grid and/or lattice structure on either the bottom sideof the separating base 276 or on a side of the separating base 276adjacent the capacitive touch sensor layer 274 to create an air gaplayer adjacent the capacitive touch sensor layer 274. In thisembodiment, the printed art layer 272 includes the capacitive touchsensor layer 274. In other embodiments, printed art layer 272 and thecapacitive touch sensor layer 274 may be separate layers as describedabove.

FIG. 24 shows an exploded view of a doll house 280 construction withcapacitive touch sensor layers 282 and a separation base 284. Thecapacitive touch sensor layers 282 is coupled to floor 285 and interiorwalls 286 of the doll house 280. by lamination, glue or similar method.The separation base 284 is coupled to outside decorative walls 289 ofthe doll house 280 by lamination, glue or similar method.

The separation base 284 is a cut or molded grid and/or latticestructure. The separation base 284 is coupled to the floor 285 andinterior walls 286 to form an air gap layer adjacent the capacitivetouch sensor layers 282. The separation base 284 mitigates thecapacitive sensor sensitivity to lower the risk of false and/orunintentional capacitive sensor triggering.

FIGS. 24A and 24B illustrate a capacitive drum set 290 with a separationbase. The capacitive drum set 290 has a printed art layer 292, acapacitive touch sensor layer 294, a plastic drum platform 296, aseparation base 298, an electronics package 300, and a speaker 302. Theseparation base 298 may be constructed/molded in plastic with a lattice,corrugated or other structure formed therein to create an air-gap layerbehind the capacitive touch sensor layer 294. This air gap layer willmitigate the capacitive sensor sensitivity to reduce the risk o falseand/or unintentional capacitive sensor triggering. Alternately, asillustrated by FIG. 24B, the capacitive touch sensor layer 294 iscombined in the printed art layer 292 with both full color printing onthe front side and the screen printed capacitive elements on thebackside or underside. For both embodiments, the plastic drum platformmay serve as the separation layer between the capacitive touch sensorlayer 294 and the separation base 298.

FIG. 31A illustrates a greeting card 310 with a separation base 316. Thegreeting card 310 includes a printed art layer 312 with a capacitivetouch sensor layer 314 integrated therein, a card backing layer 317, andan electronics package 318. In this embodiment, the separation base 316is molded in plastic with a lattice structure, but in other embodiments,other materials such as paper may be used and other structure geometriesmay be used, such as a corrugated structure, or any other structure thatwill create an air gap layer behind the capacitive touch sensor layer314. The shielding of the capacitive touch sensor layer 314 is animportant feature for the greeting card to function properly as agreeting card is hand held when it is operated. The inclusion of theseparation base 316 creates an air gap layer behind the capacitive touchsensor layer 314 that will mitigate false and/or unintentionaltriggering of thin film capacitive touch sensors in the capacitive touchsensor layer 314 from the back side of the greeting card 310 when thegreeting card 310 is being held.

FIGS. 25B and 25C illustrate a greeting card 320 with an interactivecapacitive folding pop-up 322. The greeting card 320 also has a card top324, a card bottom 326 and an electronic package 334. The pop-up 322comprises a printed art layer 330 and a capacitive touch sensor layer332. In some embodiments, the capacitive touch sensor layer 332 iscombined with the printed art layer 330 in a common layer. When thegreeting card 320 is opened, an air gap layer 328 is created between thepop-up 322 and the card top 324. The air gap layer 328 formed behind thecapacitive touch sensor layer 332 of the pop-up 322 mitigate thecapacitive sensor sensitivity to false and/or unintentional capacitivesensor triggering from touches to the back of the capacitive touchsensor layer 332, in particular as the greeting card is grasped in byhand.

FIG. 26A illustrates a capacitive guitar 340 embodiment constructionusing an air gap layer 344 and a conductive ground plane layer 350. Thecapacitive guitar 340 also comprises a guitar body 342, a guitar neck348, a neck housing 346, a separation layer 352, a printed art layer354, capacitive touch sensor layer 356, an electronics package 358 and aspeaker 359. In this embodiment, both the conductive ground plane layer350 and the air gap layer 344 are used because of the product's physicaldesign. This is possible because of the neck housing 346 creates the airgap layer 344. The conductive ground plane layer 350 doesn't have aseparate housing covering the back of the entire guitar body 342, so itis mounted on the top of the guitar body 342 with separation layer 352between it and the capacitive touch sensor layer 356.

The air gap layer 344 provided in and/or formed by the neck housing 346and the conductive ground plane layer 350 provided in the guitar body342 behind the respective parts of the capacitive touch sensor layer 356mitigate the capacitive sensor sensitivity to false and/or unintentionalcapacitive sensor triggering. In the embodiment shown in FIG. 26A, theprinted art layer 354 and the capacitive touch sensor layer 356 areseparate. In an alternate embodiment, as illustrated by FIG. 26B thecapacitive touch sensor layer 356 is combined with the printed art layer354, with thin film capacitive touch sensors screen printed or otherwiseformed on the underside or backside of the printed art layer 354.

Though illustrated and described with reference to board games, greetingcards, and instruments (e.g., guitars and drums) it is to be understoodthat thin film capacitive touch sensors including a conductive groundplane layer shield, air gap layer shield, and/or a combination thereof,may be included in any device or product to make the device or producttouch sensitive and/or touch interactive. For example, clothes(including doll clothes), fabrics, accessories, and the like may includeone or more thin film capacitive touch sensors. Further, posters andother print advertising materials may include one or more thin filmcapacitive touch sensors.

Further, the capacitive touch sensor layer need not be a planar layer.For example, the capacitive touch sensor layer (and any ground planeshield layer and/or air gap layer) may be formed in a non-planarconfiguration. Further, for a substantially enclosed non-planarconfiguration (e.g., a bottle, can, or other container), the interior ofthe container may serve as the air gap layer to substantially mitigateor prevent false and/or unintentional capacitive sensor triggering.

As noted above, the thin film capacitive touch sensors may interact withany variety of electronic circuits or devices as input devices. Forexample, the electronic circuits or devices may include radio frequencyand/or other wireless interface circuits or devices so that theelectronic circuit may be remotely controlled and/or provide a wirelesssignal indicative of the state of the thin film capacitive touchsensors.

Those skilled in the art will recognize that numerous modifications andchanges may be made to the preferred embodiment without departing fromthe scope of the claimed invention. It will, of course, be understoodthat modifications of the invention, in its various aspects, will beapparent to those skilled in the art, some being apparent only afterstudy, others being matters of routine mechanical, chemical andelectronic design. No single feature, function or property of thepreferred embodiment is essential. Other embodiments are possible, theirspecific designs depending upon the particular application. As such, thescope of the invention should not be limited by the particularembodiments herein described but should be defined only by the appendedclaims and equivalents thereof.

I claim:
 1. A touch sensitive sensor system comprising: a capacitivetouch sensor layer; a separation layer adjacent the capacitive touchsensor layer; and a conductive ground plane layer adjacent theseparation layer configured to shield a backside of the capacitive touchsensor layer.
 2. The touch sensitive sensor system of claim 1, theseparation layer further comprising a dielectric material at leastapproximately 0.5 mm thick.
 3. The touch sensitive sensor system ofclaim 1, the capacitive touch sensor layer further comprising acapacitive element deposed on a thin film substrate, the capacitiveelement comprising conductive ink printed on a thin film substrate. 4.The touch sensitive sensor system of claim 3, the capacitive elementfurther comprising a conductive ink grid having less than completeconductive ink coverage.
 5. The touch sensitive sensor system of claim4, the conductive ink grid further having 50% or greater coverage. 6.The touch sensitive sensor system of claim 4, the conductive ink gridfurther having 35% or greater coverage.
 7. The touch sensitive sensorsystem of claim 3 further comprising a printed art layer adjacent thecapacitive touch sensor layer and opposite the separation layer.
 8. Thetouch sensitive sensor system of claim 7 wherein the capacitive touchsensor layer is integrally formed in the printed art layer.
 9. The touchsensitive sensor system of claim 8, the printed art layer furthercomprising an opaque layer disposed between printed artwork and thecapacitive touch sensor layer.
 10. The touch sensitive sensor system ofclaim 1, the capacitive touch sensor layer further comprising asubstantially one-sided capacitive touch sensor layer shielded by theconductive ground plane layer.
 11. The touch sensitive sensor system ofclaim 10, the one-sided capacitive touch sensor layer configured tosubstantially prevent sensing a touch on the backside of the touchsensitive sensor system.
 12. The touch sensitive sensor system of claim11, the conductive ground plane layer further comprising a conductiveink grid having less than complete conductive ink coverage.
 13. A touchsensitive sensor system comprising: a capacitive touch sensor layer; andan art layer coupled to the capacitive touch sensor layer.
 14. The touchsensitive sensor system of claim 13 wherein the art layer is coupled tothe capacitive touch sensor layer by lamination.
 15. The touch sensitivesensor system of claim 13 wherein the art layer is coupled to thecapacitive touch sensor layer by gluing.
 16. The touch sensitive sensorsystem of claim 13, the capacitive touch sensor layer further comprisingconductive ink printed on a thin film substrate.
 17. The touch sensitivesensor system of claim 16, wherein the conducted ink is printed on thethin film substrate in a grid having less than complete conductive inkcoverage.
 18. A touch sensitive sensor system comprising: a thin filmsubstrate; and a capacitive element of conductive ink deposed on thethin film substrate.
 19. The touch sensitive sensor system of claim 18further comprising art work printed on the thin film substrate.
 20. Thetouch sensitive sensor system of claim 18 further comprising an opaquelayer printed on the thin film substrate between the thin film substrateand the capacitive element of conductive ink.
 21. The touch sensitivesensor system of claim 18, wherein the capacitive element of conductiveink is deposed on the thin film in grid having less than completeconductive ink coverage.